The 3.03 efficiency number is probably valid. The distinction is that manufacturers often use an integrated sphere for that calculation.
Essentially, every photon emitted from the light is counted.
While legit, it's not the same as as PPFD hitting a flat surface.
Probably closer to 2.8 in a real-world PAR measurement.
Many of them just quote nominal current efficiency of the diodes or board efficiency. 3.03 with driver losses and 1000w isnt easy, youd need an absurd amount of diodes. HLG does it with about 4000 diodes for 650w (iirc), but they seem to have all the best bins and drivers. Count the diodes, and evaluate the price and extrapolate.
I dunno, fudging on numbers seems quite common right now. A few have externally confirmable reports but with most just come with a report from the manufacturer, a little file with some graphs. Especially with the china lights and rebrands.
On the photontek id doubt a very high "migro" numbers; its ppfd on cannopy in average:
To get to 2.8 youd have to have an average of 1400 ppfd; the average is lower to be fair.
Maybe around 1000 and a bit, guesstimating centre values vrs corners.
These large bar lights are not allways ideal, if they have to hang too high they get a hotspot and usually bad coverage in the sides. But its a size and layout versus wattage thing.
The king brite light lets you play with the bars which is nice. Also they look diy amendable, kingbrite have nice gear for that, like adding uv and far red.
But if youre getting a good deal on the hlg 350s that is probably what id choose. If its too many for raising/lowering just do your own home made scorpion to whatever dimension and weight that suits you.